Journal cover Journal topic
Hydrology and Earth System Sciences An interactive open-access journal of the European Geosciences Union
doi:10.5194/hess-2017-9
© Author(s) 2017. This work is distributed
under the Creative Commons Attribution 3.0 License.
Research article
17 Jan 2017
Review status
This discussion paper is under review for the journal Hydrology and Earth System Sciences (HESS).
Bayesian joint inference of hydrological and generalized error models with the enforcement of Total Laws
Mario R. Hernández-López and Félix Francés Research Institute of Water and Environmental Engineering, Universitat Politècnica de València, Spain
Abstract. Over the years, the Standard Least Squares (SLS) has been the most commonly adopted criterion for the calibration of hydrological models, despite the fact that they generally do not fulfill the assumptions made by the SLS method: very often errors are autocorrelated, heteroscedastic, biased and/or non-Gaussian. Similarly to recent papers, which suggest more appropriate models for the errors in hydrological modeling, this paper addresses the challenging problem of jointly estimate hydrological and error model parameters (joint inference) in a Bayesian framework, trying to solve some of the problems found in previous related researches. This paper performs a Bayesian joint inference through the application of different inference models, as the known SLS or WLS and the new GL++ and GL++Bias error models. These inferences were carried out on two lumped hydrological models which were forced with daily hydrometeorological data from a basin of the MOPEX project. The main finding of this paper is that a joint inference, to be statistically correct, must take into account the joint probability distribution of the state variable to be predicted and its deviation from the observations (the errors). Consequently, the relationship between the marginal and conditional distributions of this joint distribution must be taken into account in the inference process. This relation is defined by two general statistical expressions called the Total Laws (TLs): the Total Expectation and the Total Variance Laws. Only simple error models, as SLS, do not explicitly need the TLs implementation. An important consequence of the TLs enforcement is the reduction of the degrees of freedom in the inference problem namely, the reduction of the parameter space dimension. This research demonstrates that non-fulfillment of TLs produces incorrect error and hydrological parameter estimates and unreliable predictive distributions. The target of a (joint) inference must be fulfilling the error model hypotheses rather than to achieve the better fitting to the observations. Consequently, for a given hydrological model, the resulting performance of the prediction, the reliability of its predictive uncertainty, as well as the robustness of the parameter estimates, will be exclusively conditioned by the degree in which errors fulfill the error model hypotheses.

Citation: Hernández-López, M. R. and Francés, F.: Bayesian joint inference of hydrological and generalized error models with the enforcement of Total Laws, Hydrol. Earth Syst. Sci. Discuss., doi:10.5194/hess-2017-9, in review, 2017.
Mario R. Hernández-López and Félix Francés
Mario R. Hernández-López and Félix Francés
Mario R. Hernández-López and Félix Francés

Viewed

Total article views: 433 (including HTML, PDF, and XML)

HTML PDF XML Total BibTeX EndNote
372 57 4 433 2 5

Views and downloads (calculated since 17 Jan 2017)

Cumulative views and downloads (calculated since 17 Jan 2017)

Viewed (geographical distribution)

Total article views: 433 (including HTML, PDF, and XML)

Thereof 430 with geography defined and 3 with unknown origin.

Country # Views %
  • 1

Saved

Discussed

Latest update: 24 Mar 2017
Publications Copernicus
Download
Short summary
The main idea which supports this research is considering that a joint parameter inference with an appropriate error model is necessary in hydrological modeling. In this framework, the main finding of this paper is that a joint inference, to be statistically correct, must take into account the joint probability distribution of the state variable to be predicted and its deviation from the observations. This is a necessary condition which can be taken into account by the Total Laws.
The main idea which supports this research is considering that a joint parameter inference with...
Share